2010 Cadillac CTS Sedan AWD V6-3.6L Page 1075
瀚慖f the test lamp does not illuminate, test the ignition circuit for an open/high resistance.
5. If all circuits/connections test normal, replace the K20 ECM.
Repair Instructions
Perform the Diagnostic Repair Verification (See: Verification Tests) after completing the diagnostic procedure.
* T8 Ignition Coil Replacement - Bank 1 (See: Powertrain Management/Ignition System/Ignition Coil/Service and Repair/Ignition Coil
Replacement - Bank 1)
* T8 Ignition Coil Replacement - Bank 2 (See: Powertrain Management/Ignition System/Ignition Coil/Service and Repair/Ignition Coil
Replacement - Bank 2)
* Control Module References (See: Testing and Inspection/Programming and Relearning) for K20 ECM replacement, setup, and
programming
P135B
DTC P135A or P135B (LF1)
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic System
Check - Vehicle) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Strategy Based Diagnosis) for an
overview of the diagnostic approach.
* Diagnostic Procedure Instructions (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic Procedure
Instructions) provides an overview of each diagnostic category.
DTC Descriptors
DTC P135A
- Ignition Coil Supply Voltage Circuit Bank 1
DTC P135B
- Ignition Coil Supply Voltage Circuit Bank 2
Diagnostic Fault Information
Circuit/System Description
The ignition system on this engine uses an individual module/coil for each cylinder. The engine control module (ECM) monitors the ignition
voltage from the fuse of each bank of coils to the ECM. The ECM uses this information to determine if the misfire is ignition coil voltage related.
Conditions for Running the DTC
* The ignition is ON.
* The ignition module supply voltage is less than 2.5 V.
* The DTCs run continuously when the above condition is met.
Conditions for Setting the DTC
The ECM detects a fault in an ignition coil control circuit for 50 out of 63 samples. Each sample runs on a 6.25 ms loop.
Action Taken When the DTC Sets
DTCs P135A and P135B are Type A DTCs.
Conditions for Clearing the DTC
DTCs P135A and P135B are Type A DTCs.
